Ed, as I recall this engine was overheated quite some time ago to the

point of

your having to replace the warped rear rotor housings. As I also recall

this was

caused by air being trapped in the water jacket due in part to inadequate
water jacket venting in the plugs up position. Also you had an oil cooling
problem for awhile. Did you replace the apex seal springs when you

overhauled

this engine? Sorry if this sounds like the third degree. I am just trying
to learn from this experience.

Weak apex seal springs in conjunction with the rust or gum from the

evaporated

gasoline could have caused the apex seals to stick. Have you tried

spraying

an apex seal through the exhaust port with WD 40 and then trying to move

it

in or out?

I would also take a small sample of the gasoline and two cycle oil mix you

use

and let it evaporate in a glass dish. Then try various solvents on the

residue

if any.

Paul Lamar

Paul,
Your recollection is correct.  The engine was overheated earlier in the test
stage and I replaced the rear rotor housing as well as the water and oil
"O" rings.  I measured the apex seal spring height and seal diminsions and
all were well within the specifications so did not replace them. However, if
the apex seal springs were weak, I would think it would be easier to depress
the seals throught the exhaust opening and they will not budge. They are
definitedly stuck.  The engine operated just fine until the flooding
incident with so much compression you could only spin the prop through one
rotor face on a pull.

I could be wrong but I am convinced that the seal sticking is related to the
flooding and subsequent long period of time I let it sit (5 weeks).  Since
it has sat for as long as 4 months with no seal sticking problem this leads
me to believe that flooding removed oil and  the light rust I see on the
rotors near the apex seal was the results.

I have not tried WD-40 and may do that after I replace the engine and see if
that frees up the valves.

Ed

They could be stuck all the way down although that is unlikely.
I guess you have the engine half out of there so at this point why they are
stuck seems to be academic. I hope we can all learn from this.
I am surprised mixing the oil with the fuel and then having
a rich mixture wash the insides of the engine sounds conflicting.
I would think for every gallon of gas that went in one ounce
of oil also went it. Ken mentioned he only found one brand of
two cycle oil that separated from the fuel. What kind are you 
using? 

I can see if the gas/oil mixture evaporated it might
leave a residue that could stick the seals. What is your hangar
like? Is it open to the elements. Perhaps I live out here
in the dry desert and have forgotten what is like in the rainy East :-)

Paul Lamar
 
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